The bill includes renewable electricity standards, emissions reductions, a system for trading emissions permits and carbon offsets, investments in energy technology (unfortunately including "clean coal") and energy efficiency standards. The bill sets target reductions of greenhouse gas emission of 42% by 2030 and more than 80% by 2050.

Opponents of Waxman-Markey, when not denying that global warming is real, are resorting to another time-honoured tactic of scaring people with wildly inflated cost estimates. Fortified with alarming numbers from thinktanks, opponents are calling the bill a "tax-and-trade" scheme that would saddle families with an unbearable financial burden for decades.

One source of these spurious numbers, the Heritage Foundation, claims that Waxman-Markey would reduce GDP by a total of $7.4tn and destroy 1.9 million jobs by the year 2035. A family's electricity bill would climb 90% and natural gas prices would climb 55%, adding $1,500 to the family budget. An even scarier assertion that the bill would cost families $3,100 was purportedly based on an MIT study – a claim that one of the study's authors, John Reilly, roundly disputed.

Opponents reached these conclusions by exaggerating the downside and ignoring the upside altogether. They have overstated the costs of renewable energy, underestimated the future costs of fossil fuels and left out the cost savings of improving energy efficiency. The Heritage Foundation report projects home energy prices will increase three to four times faster than the Congressional Budget Office or Environmental Protection Agency studies, and doesn't include any benefits from improvements in energy efficiency or investing in new industries.

These savings will come by investing in renewable energy technologies that won't be subject to the relentless and inexorable increase in fossil fuel prices. The EPA projects that by 2025 two thirds of new energy generation will be from renewable sources.

There is one important factor the Heritage, CBO and EPA analyses all leave out: the cost of unchecked global warming, which could be considerable. Global warming will do more than inconvenience a few polar bears. Reduced snow melts in the Rockies and the Himalayas could disrupt agricultural water supplies in the US, China and India.

As more water is released from ice caps and mountain ranges, rising sea levels could force the relocation of significant populations and disrupt important infrastructure. Here in Delaware, rising sea levels could flood the principal highway and rail line connecting New York and Washington. Water and sewer service for more than half of Delaware's residents could be rendered unsafe or shut down altogether.

A bill this complex on a subject this important deserves careful review. But opponents of Waxman-Markey have resorted to distorted analysis, one-sided arguments and crass exaggerations to make the case that we can't afford to act. More careful – and balanced – analysis leads to the opposite conclusion that can't afford to wait.